If you BYO microSD card, you can get AndroidForNook's Jelly Bean deployment for as little as $9.99.
AndroidForNook

I know from response to past posts that there's a lot of interest in rooting Barnes & Noble's Nook tablets (specifically the Nook Color, Nook Tablet, Nook HD, and Nook HD+). And why not? The hardware is great, but B&N's heavily modded interface curtails many of Android's best features -- not the least of which is access to Google Play and all the apps, movies, TV shows, and games therein.

Tech-savvy users can "root" a Nook to run Android proper, and the even tech-savvier ones can make a Nook run Android from a microSD card (thus keeping the original B&N software intact). If you don't have those skills, or just don't want to risk bricking your tablet, several companies offer Nook-to-Android solutions.

It works like this: you download the proper AFN image for your tablet, then run an executable to load it onto your microSD card. The developer strongly recommends using a SanDisk Class 4 card, which is what I used for testing. To give you some idea as to pricing, Newegg sells a 16GB SanDisk card for $12.99 shipped.

Once the installer copies the image file to your card, you simply pop it into your Nook and reboot. In a minute, presto: you've got Android Jelly Bean. AFN is like N2A Cards in that you get a very bare-bones distribution, which is a little dull, but good if you don't like shovelware. Stock the tablet with only those apps you want.

The only downside I could see, and it's a minor one, is that AFN doesn't yet offer a dual-boot option: if you want to go back to using the Nook OS, you have to power down, pop the card out, and reboot. Root My Nook and N2A Cards both give you the option of loading a boot menu, then choosing the OS you want to load. (Update:The Nook Color and Nook Tablet cards/downloads do offer dual-boot, and the developer notes that the HD and HD+ versions will in the future.)

If you've been wanting to try "the full Android" on your Nook tablet but didn't want to shell out much money for the privilege, AndroidForNook answers the call for a sawbuck. And there's a fairly active user forum where you can learn more and get help if needed.